﻿using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace AdoNetTest0002
{
    class DbHelper
    {
        private static readonly string connectionString = "server=.;database=Admin3000;uid=sa;pwd=123456";


        public static SqlDataReader Query(string cmdString)
        {

            SqlConnection sqlConnection = new SqlConnection(connectionString);

            using (SqlCommand cmd=new SqlCommand(cmdString, sqlConnection))
            {

                sqlConnection.Open();
                return cmd.ExecuteReader(CommandBehavior.CloseConnection);
            }
            
        }

        public static int Operate(string cmdString)
        {
            SqlConnection sqlConnection = new SqlConnection(connectionString);

            using (SqlCommand cmd = new SqlCommand(cmdString, sqlConnection))
            {

                sqlConnection.Open();
                return cmd.ExecuteNonQuery();
            }

        }

        public static DataTable GetDataTable(string cmdString)
        {
            SqlConnection sqlConnection = new SqlConnection(connectionString);

            SqlDataAdapter dataAdapter = new SqlDataAdapter(cmdString,connectionString);
            DataTable table = new DataTable();
            dataAdapter.Fill(table);
            return table;
        }
    }
}
